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991.
Brennan P Pescatello LS Bohannon RW Marschke L Murphy M Coble D Hasson S 《Preventive cardiology》2005,8(3):160-164
Isolated systolic hypertension is present in the majority of older women. Exercise is an attractive antihypertensive lifestyle therapy for older women with isolated systolic hypertension, but the amount of exercise needed to reduce blood pressure (BP) is not clear. Evidence is accumulating that lower levels of physical exertion are associated with decreased BP. The authors sought to determine if BP was related to daily time spent moving. Participants were 109 women (mean +/- SD, 75.2+/-7.2 yr). A majority (63.3%) had hypertension, and 48.6% had isolated systolic hypertension. Systolic BP was lower among women moving > or =5 h/d (142.2+/-18.7 mm Hg) than those moving <5 h/d (149.8+/-19.0 mm Hg) (p=0.038). Multiple regression analysis indicated that the potentially strong confounding effects of antihypertensive medication use, adiposity, and age did not eliminate these favorable associations between daily time spent moving and systolic BP. Older women should be encouraged to regularly engage in physical activities typical of everyday life such as walking because of its BP benefits. 相似文献
992.
Long axis electromechanics during dobutamine stress in patients with coronary artery disease and left ventricular dysfunction 总被引:2,自引:0,他引:2 下载免费PDF全文
Duncan AM O'Sullivan CA Carr-White GS Gibson DG Henein MY 《Heart (British Cardiac Society)》2001,86(4):397-404
OBJECTIVE—To dissociate the effect of inotropy from activation change during dobutamine stress on left ventricular long axis function in patients with coronary artery disease (CAD).
METHODS—25 patients with CAD and normal left ventricular cavity size and 30 with cavity dilatation—18 with normal activation (DCM-NA) and 12 with left bundle branch block (DCM-LBBB)—were compared with 20 controls. 12 lead ECG and septal long axis echograms were assessed at rest and peak dobutamine stress. Amplitude, shortening and lengthening velocities, postejection shortening, Q wave to onset of shortening (Q-OS), and A2 to onset of lengthening (A2-OL) were measured. Inotropy was evaluated from peak aortic acceleration.
RESULTS—In controls, amplitude, shortening and lengthening velocities, and peak aortic acceleration increased with stress; QRS, Q-OS, and A2-OL shortened (all p < 0.001); and contraction remained coordinate. In the group of patients with CAD and normal left ventricular cavity size, shortening velocity and peak aortic acceleration increased with stress (p < 0.005). However, amplitude and lengthening velocity did not change, QRS, Q-OS, and A2-OL lengthened (p < 0.01), and incoordination appeared. Results were similar in the group with DCM-NA. In the DCM-LBBB group, shortening velocity and peak aortic acceleration increased modestly with stress (p < 0.01) but amplitude, lengthening velocity, QRS, Q-OS, A2-OL, and incoordination remained unchanged. Overall, change in shortening velocity correlated with that in peak aortic acceleration (r2 = 0.71), in amplitude with that in lengthening velocity (r2 = 0.74), and in QRS with both Q-OS (r2 = 0.69) and A2-OL (r2 = 0.63).
CONCLUSION—The normal long axis response to dobutamine reflects both inotropy and rapid activation. In CAD, inotropy is preserved with development of ischaemia but the normal increase in amplitude is lost and prolonged activation delays the time course of shortening, causing pronounced incoordination. Overall, shortening rate uniformly reflects inotropy while lengthening rate depends mainly on systolic amplitude rather than primary diastolic involvement, even with overt ischaemia.
Keywords: stress echocardiography; activation; inotropy; incoordination 相似文献
METHODS—25 patients with CAD and normal left ventricular cavity size and 30 with cavity dilatation—18 with normal activation (DCM-NA) and 12 with left bundle branch block (DCM-LBBB)—were compared with 20 controls. 12 lead ECG and septal long axis echograms were assessed at rest and peak dobutamine stress. Amplitude, shortening and lengthening velocities, postejection shortening, Q wave to onset of shortening (Q-OS), and A2 to onset of lengthening (A2-OL) were measured. Inotropy was evaluated from peak aortic acceleration.
RESULTS—In controls, amplitude, shortening and lengthening velocities, and peak aortic acceleration increased with stress; QRS, Q-OS, and A2-OL shortened (all p < 0.001); and contraction remained coordinate. In the group of patients with CAD and normal left ventricular cavity size, shortening velocity and peak aortic acceleration increased with stress (p < 0.005). However, amplitude and lengthening velocity did not change, QRS, Q-OS, and A2-OL lengthened (p < 0.01), and incoordination appeared. Results were similar in the group with DCM-NA. In the DCM-LBBB group, shortening velocity and peak aortic acceleration increased modestly with stress (p < 0.01) but amplitude, lengthening velocity, QRS, Q-OS, A2-OL, and incoordination remained unchanged. Overall, change in shortening velocity correlated with that in peak aortic acceleration (r2 = 0.71), in amplitude with that in lengthening velocity (r2 = 0.74), and in QRS with both Q-OS (r2 = 0.69) and A2-OL (r2 = 0.63).
CONCLUSION—The normal long axis response to dobutamine reflects both inotropy and rapid activation. In CAD, inotropy is preserved with development of ischaemia but the normal increase in amplitude is lost and prolonged activation delays the time course of shortening, causing pronounced incoordination. Overall, shortening rate uniformly reflects inotropy while lengthening rate depends mainly on systolic amplitude rather than primary diastolic involvement, even with overt ischaemia.
Keywords: stress echocardiography; activation; inotropy; incoordination 相似文献
993.
Relation between electrocardiographic repolarisation changes and mechanical events in left ventricular hypertrophy. 下载免费PDF全文
The relation between ventricular function and the presence of electrocardiographic "strain" in patients with left ventricular hypertrophy was examined using digitised M mode echocardiography and 12 lead electrocardiograms in 64 patients with pressure overload, 21 with hypertrophic cardiomyopathy, and 14 athletes. Although all had increased left ventricular mass, those with strain had a prolonged interval from minimum cavity dimension to mitral valve opening and a reduced rate of early diastolic posterior wall thinning and dimension increase compared with those with normal ST segments and T waves. Both groups had normal systolic function (fractional shortening and peak velocity of circumferential fibre shortening), and the time between the termination of the T wave and minimum dimension was similar. In athletes, however, electromechanical systole was shorter than normal, and the end of the T wave and minimum cavity dimension were synchronous. It is concluded that abnormal electrical recovery in left ventricular hypertrophy is closely related to impaired early relaxation and may be dissociated from impaired systolic function, cavity dimension, interventricular conduction delay, and the presence of increased mass alone. The normal relation between electrical and mechanical systole is preserved even when the polarity of repolarisation is reversed. 相似文献
994.
995.
996.
Linda Lee George Heckman Robert McKelvie Philip Jong Teresa D’Elia Loretta M. Hillier 《Canadian family physician Médecin de famille canadien》2015,61(3):e148-e157
Objective
To explore the barriers to and facilitators of adapting and expanding a primary care memory clinic model to integrate care of additional complex chronic geriatric conditions (heart failure, falls, chronic obstructive pulmonary disease, and frailty) into care processes with the goal of improving outcomes for seniors.Design
Mixed-methods study using quantitative (questionnaires) and qualitative (interviews) methods.Setting
Ontario.Participants
Family physicians currently working in primary care memory clinic teams and supporting geriatric specialists.Methods
Family physicians currently working in memory clinic teams (n = 29) and supporting geriatric specialists (n = 9) were recruited as survey participants. Interviews were conducted with memory clinic lead physicians (n = 16). Statistical analysis was done to assess differences between family physician ratings and geriatric specialist ratings related to the capacity for managing complex chronic geriatric conditions, the role of interprofessional collaboration within primary care, and funding and staffing to support geriatric care. Results from both study methods were compared to identify common findings.Main findings
Results indicate overall support for expanding the memory clinic model to integrate care for other complex conditions. However, the current primary care structure is challenged to support optimal management of patients with multiple comorbidities, particularly as related to limited funding and staffing resources. Structured training, interprofessional teams, and an active role of geriatric specialists within primary care were identified as important facilitators.Conclusion
The memory clinic model, as applied to other complex chronic geriatric conditions, has the potential to build capacity for high-quality primary care, improve health outcomes, promote efficient use of health care resources, and reduce health care costs. 相似文献997.
998.
Linda Springvloet Lilian Lechner Hein de Vries Math JJM Candel Anke Oenema 《Journal of medical Internet research》2015,17(1)
Background
Web-based, computer-tailored nutrition education interventions can be effective in modifying self-reported dietary behaviors. Traditional computer-tailored programs primarily targeted individual cognitions (knowledge, awareness, attitude, self-efficacy). Tailoring on additional variables such as self-regulation processes and environmental-level factors (the home food environment arrangement and perception of availability and prices of healthy food products in supermarkets) may improve efficacy and effect sizes (ES) of Web-based computer-tailored nutrition education interventions.Objective
This study evaluated the short- and medium-term efficacy and educational differences in efficacy of a cognitive and environmental feedback version of a Web-based computer-tailored nutrition education intervention on self-reported fruit, vegetable, high-energy snack, and saturated fat intake compared to generic nutrition information in the total sample and among participants who did not comply with dietary guidelines (the risk groups).Methods
A randomized controlled trial was conducted with a basic (tailored intervention targeting individual cognition and self-regulation processes; n=456), plus (basic intervention additionally targeting environmental-level factors; n=459), and control (generic nutrition information; n=434) group. Participants were recruited from the general population and randomly assigned to a study group. Self-reported fruit, vegetable, high-energy snack, and saturated fat intake were assessed at baseline and at 1- (T1) and 4-months (T2) postintervention using online questionnaires. Linear mixed model analyses examined group differences in change over time. Educational differences were examined with group×time×education interaction terms.Results
In the total sample, the basic (T1: ES=–0.30; T2: ES=–0.18) and plus intervention groups (T1: ES=–0.29; T2: ES=–0.27) had larger decreases in high-energy snack intake than the control group. The basic version resulted in a larger decrease in saturated fat intake than the control intervention (T1: ES=–0.19; T2: ES=–0.17). In the risk groups, the basic version caused larger decreases in fat (T1: ES=–0.28; T2: ES=–0.28) and high-energy snack intake (T1: ES=–0.34; T2: ES=–0.20) than the control intervention. The plus version resulted in a larger increase in fruit (T1: ES=0.25; T2: ES=0.37) and a larger decrease in high-energy snack intake (T1: ES=–0.38; T2: ES=–0.32) than the control intervention. For high-energy snack intake, educational differences were found. Stratified analyses showed that the plus version was most effective for high-educated participants.Conclusions
Both intervention versions were more effective in improving some of the self-reported dietary behaviors than generic nutrition information, especially in the risk groups, among both higher- and lower-educated participants. For fruit intake, only the plus version was more effective than providing generic nutrition information. Although feasible, incorporating environmental-level information is time-consuming. Therefore, the basic version may be more feasible for further implementation, although inclusion of feedback on the arrangement of the home food environment and on availability and prices may be considered for fruit and, for high-educated people, for high-energy snack intake.Trial Registration
Netherlands Trial Registry NTR3396; http://www.trialregister.nl/trialreg/admin/rctview.asp?TC=3396 (Archived by WebCite at http://www.webcitation.org/6VNZbdL6w). 相似文献999.
Ingrid?EitzenEmail author Linda?Fernandes Lars?Nordsletten May?Arna?Risberg 《Journal of negative results in biomedicine》2015,14(1):5
Background
It is unknown whether gait biomechanics in hip osteoarthritis patients with mild to moderate symptoms change following exercise therapy interventions. The aim of the present study was to compare stance phase gait characteristics in hip osteoarthritis patients with mild to moderate symptoms participating in a randomized trial with two different interventions; patient education only or patient education followed by a 12-week supervised exercise therapy program.Results
The study was conducted as a secondary analysis of a single-blinded randomized controlled trial. Patients aged 40 to 80 years, with hip osteoarthritis verified from self-reported pain and radiographic changes, were included. The final material comprised 23 patients (10 males/13 females, mean (SD) age 58.2 (10.02) years) in the patient education only group, and 22 patients (9 males/13 females, mean (SD) age 60.2 (9.49) years) in the patient education + exercise therapy group. Three-dimensional gait analysis was conducted at baseline and at four month follow-up. Sagittal and frontal plane joint angle displacement and external joint moments of the hip, knee and ankle were compared from a one-way analysis of covariance between the groups at follow-up, with baseline values as covariates (p < 0.05). No group differences were observed at the four-month follow-up in gait velocity, joint angle displacement, or moments. As the compliance in the exercise therapy group was inadequate, we calculated possible associations between the number of completed exercise sessions and change in each of the kinematic or kinetic variables. Associations were weak to neglible. Thus, the negative findings in this study cannot be explained from inadequate compliance alone, but most likely also suggest the exercise therapy program itself to be insufficient to engender gait alterations.Conclusions
Adding a 12-week supervised exercise therapy program to patient education did not induce changes in our selected biomechanical variables during the stance phase of gait, even when adjusting for poor compliance. Thus, we did not find evidence to support our exercise therapy program to be an efficacious intervention to induce gait alterations in this population of hip osteoarthritis patients.Trial registration
NCT00319423 at ClinicalTrials.gov (registration date 2006-04-26).1000.
Anna-Karin E Palm Heike C Friedrich Anja Mezger Maya Salomonsson Linda K Myers Sandra Kleinau 《Cellular & molecular immunology》2015,12(4):493-504
Polyreactive innate-type B cells account for many B cells expressing self-reactivity in the periphery. Improper regulation of these B cells may be an important factor that underlies autoimmune disease. Here we have explored the influence of self-reactive innate B cells in the development of collagen-induced arthritis (CIA), a mouse model of rheumatoid arthritis. We show that splenic marginal zone (MZ), but not B-1 B cells exhibit spontaneous IgM reactivity to autologous collagen II in naïve mice. Upon immunization with heterologous collagen II in complete Freund''s adjuvant the collagen-reactive MZ B cells expanded rapidly, while the B-1 B cells showed a modest anti-collagen response. The MZ B cells were easily activated by toll-like receptor (TLR) 4 and 9-ligands in vitro, inducing proliferation and cytokine secretion, implying that dual engagement of the B-cell receptor and TLRs may promote the immune response to self-antigen. Furthermore, collagen-primed MZ B cells showed significant antigen-presenting capacity as reflected by cognate T-cell proliferation in vitro and induction of IgG anti-collagen antibodies in vivo. MZ B cells that were deficient in complement receptors 1 and 2 demonstrated increased proliferation and cytokine production, while Fcγ receptor IIb deficiency of the cells lead to increased cytokine production and antigen presentation. In conclusion, our data highlight self-reactive MZ B cells as initiators of the autoimmune response in CIA, where complement and Fc receptors are relevant in controlling the self-reactivity in the cells. 相似文献